Preheat the air fryer to 360°F (182°C) and lightly spray the basket with avocado or olive oil cooking spray.
Pat the chicken breasts dry with paper towels and place them in a mixing bowl.
Pour 5 tablespoons buffalo sauce over the chicken, then season with 1/2 teaspoon salt, 1/4 teaspoon garlic powder, and 1/4 teaspoon black pepper; toss to coat evenly and let sit to marinate for 5 minutes.
Arrange the chicken in a single layer in the air fryer basket and cook at 360°F for 10 minutes.
Flip the breasts and continue cooking for another 5 minutes, or until an instant-read thermometer registers 165°F (74°C) in the thickest part.
Remove the chicken, brush with extra buffalo sauce if desired, and let rest for 5 minutes before slicing and serving with celery, carrot sticks, and blue cheese dressing if using.